Injection nozzle arrangement



INJECTION NOZZLE ARRANGEMENT 2 Shets-Sheet 1 Filed Aug. 26, 1954 INVENTOR Fey/med Meur'er' a d ATTONEYJ Jan. 15, 1957 s. MEURER INJECTIONNOZZLE ARRANGEMENT 2 Sheets-Sheet 2 Filed Aug. 26, 1954 INVENTIOYRNJz'eyf/"l'ed Meurer %,M 2 Mala;

ATTORNEYS United States Patent" 2,777,431 INJECTION NUZZLE ARRANGEMENTSiegfried Meurer, Numberg, Germany, -assignor to Maschin'enf'ahrikAugsburg-Numberg A. G'., Nurnberg,

Bavaria, Germany, a firm ApplicationAugust 26, 1954,1Serial No. 452,359Claims priority, applicationGermanyAngust 23, 1953 8' Claims. (Cl.12332-)- Insmall high speed engines, however, the nozzles are toosmallto permit such cooling.

It is an object of the persent invention to provide an arrangementensuring an efficient heat transfer from the nozzle to the surroundingparts so as to keep the nozzle temperature at a low figure.

A special object :of the invention is to provide an arrangement in whichthe nozzle surf-ace exposed to the hot gas is reduced to a minimum andan intimate heattransmitting engagement is ensured between the nozzleand its holder under all operating conditions and irrespective ofdifferent thermal expansion of said parts.

Another object of the invention is to provide an arrangement permittingeasy mounting of the nozzle and avoiding distorting stresses therein.

With these and other objects in view, this invention consists in thedetails of construction, combination of elements and operationhereinafter set forth and then specifically designated by the claims.

In order that those skilledin the art to whichv this inventionappertains may understand how tomake and use the same, I will describeits constructionin, detail, referring by numerals tothe-accompanyingdrawings formingzpart of this'application, inwhich:

Fig. 1' is a sectional viewof anarrangement having the invention appliedthereto,

Fig. 2 is -a detail thereof,

Figure 3 is a sectional view similar to Fig. 1, showing a modified form,

Fig. 4 is a view similar to Figs. 1 and 3, but showing a-furthermodification, and

Fig. 5 is a view similar to Fig. 4, showing a still'furthermodification.

:transfe-r member even at difierent thermal expansion of the parts.

This is exemplified in Fig. 1, showing a nozzle holder 1 and anozzle'-comprising a main body 3, aistem 3, a needle valve 36,. with itsextension 32, and a nozzle tip 4 with the atomizing bores (not shown),secured to the.

nozzle holder '1 by a cap nut 2 thread'ably engaged on a male thread ofthe nozzle holder The needle 30 is exposed to the pressure of aspring"(not shown)v through a; "round pressure rod 34 and.apressure-transmittingball 35 seated in a recess of the rod-34 andengaged by an:

I in a cold condition.

upper projection 32' of the extension 32 of the needle valve 30, asshown. The fuel is admitted through a channel 33, 33' in the members3and 1. Mounted on the noz-v v The intermediate member 8 is elastic orresilient in an axial direction, preferably by the provision of slots'8, Fig. 2.

It will thus be understood that the'conicalpacking memher 5 can beslipped onto the cylindrical nozzle stem 3 By way of alternative, thenozzle stem 3: may also be conically shaped.

The arrangement illustrated operates as follows:

As the'cylinder head 6 and the nozzle 3, 3" are heated during operationof the engine, thepacking body 5, having a larger thermal expansion thanthe nozzle stem 3', tends to expand, this tendency being opposed in thedirection of the nozzle holder by the resilient member 8. Owing to theconical seat of the packing body 5 in the bore 7 the body 5 isforcedtoexpandradially inwards, in sucha Way that the fit between the stem 3'and the membr 5 becomes a grip fit, the amount of specific pressurebeing determined by the resiliency of the. member 8 andthe slope of thecone 5 in the cylinder head 6, in such a way that deformation of thenozzle is avoided.

The tightengagement of the packing surfaces between the nozzle stem 3and the conical packing body 5 on the one handand between the latter andthe. cylinder head 6 is thus improved as a result of the thermalstresses. Therefore, the fuel gas is safely prevented from enteringbetween the packing-body 5 and the nozzle stem 3. and

from heating the parts in entering therebetween-and the transfer of heatfrom the nozzle stem 3' through the packing body 5 to. the cooledcylinder head 6isfiacilitated packing body 5 will be retained in thecylinder head,

by the higher specific surface pressure between the adjoining surfaces.

If the nozzle is dismantled in a hot condition of the engine, thepacking body 5 will be removed from-the cylinder head 6 together withthe nozzle 3, 3', in view of the grip fit between the members 5 and 3,in a hot condition. 011 the other hand, if the nozzle is removed withthe cylinder head 6 in cold condition, the conical so-that the nozzle 3,3 can be withdrawn from the member 5.

According to a modified form of the invention the conical packing bodyis provided with a sleeve-shaped extension which in the built-incondition of the nozzle is washed by the cooling Water circulating inthe doublewalled cylinder head, for ensuring antefiicient cooling.

According to a still further feature of the invention, the conicalpacking body may be designed inpsucha: way that it retains the nozzlestem after the manner. of. a chuck, whereby deformations or distortionstresses of the nozzle can be easily avoided, without requiring a highaccuracy ofmanufacture. Thus, an elastic sleeve member such as thatprovided at 3 in Fig. 1 for compensating possible. inaccuracies is notrequired.

An arrangement of this kind is illustrated in Fig. 3', the extensionbeing shown at 11 In order to prevent. the cooling water from enteringinto thecylinder 6 wh'ei1 removing the nozzle 3, 3 the: packing inemberSis exposed toa preliminary pressure by the ring mu T4 through theextension n and a further intermediate 'sieeve 1a, the

Patented Jan. 15, 1957 i packing efiect at 10 again being ensured bytight engagement between the cap nut 2 and the upper face of the packingbody 5, said engagement being caused by the nozzle holder 1 in a mannernot shown in detail. Additional packing rings 15 and 16 may be providedbetween the parts 11 and 13, or 13 and 14, respectively.

A still further and preferred modification is exemplified in Fig. 4.Again, the packing cone 5' is formed with an extension 17, which in thiscase projects into the nozzle holder 1, for urging the cone 5 into theconical seat 7 1 of the cylinder head 6 by the ring nut 9 through anintermediate disc 18 and an expanding ring 19, which may be a springring or a bipartite ring. The bore in the cone 5 is thus contracted, sothat the nozzle stem 3 is clamped as in a chuck. The gas-tightness inthis case is ensured already by the pressure between the nozzle stem 3'and the packing cone 5 and faulty gripping of the nozzle holder 1 andthe nozzle cannot occur, since the nozzle holder, the same as in Fig. 3,automatically adjusts itself strictly in accordance with the bore in thepacking cone 5. However, as distinguished from Fig. 3, additional meansin the form of intermediate rings or a helical spring 2d are provided toprevent the nozzle holder 1 from being inadvertently forced out of thebore, said rings or helical spring 20 engaging the cap nut 21 if the gaspressure should tend to force the nozzle body 3 outwards owing to apossible too loose connection erroneously existing between the members 5and 3'. A rubber ring 21 prevents the cooling water from entering intothe cylinder when dimantling the nozzle. The conical seating surface ofmember 3 is subdivided into two or more ring surfaces by the provisionof one or more turned-in annular grooves 22, whereby the adaptationbetween the cone 5 and the conical bore 7 is improved without impairingthe gas-tight seal or the heat transfer.

The spreader or expanding ring 19 which is free to move axially in itsrecess 19a in the cylinder head 6 in an axial direction towards thenozzle, but held against such axial movement in an opposite direction,prevents the cone member 5 from being inadvertently withdrawn from thecylinder head 6 in an upward direction when withdrawing the nozzleholder 1.

It will thus be understood that in the embodiment shown in Fig. 4 thecone 5 is positively pressed onto its seat 7 through the parts 9, 18,3.9, 17, and additionally it is nonpositively pressed onto its seat 7through the members 9, 20, 2 and the engagement at 10.

If the ring nut 9 is removed, for withdrawing the nozzle, only themember 20 and possibly, but not necessarily, the ring 13, will take partin such withdrawing movement, while the expanding ring 19 remains in itsposition, or engages the shoulder formed at the end of the recess 19a,respectively, thus retaining the member 17 and the cone member 5 inposition. Hence, even when withdrawing the nozzle, cooling water cannever penetrate into the combustion chamber.

In the modification shown in Fig. 5 a separate member 17' is seated in acylindrical stepped bore in the cylinder head 6 and held in its positionby axial pressure exerted by a threaded ring 9, through rings 18 and 19.The conical member 5 in this case is seated in a complementary conicalbore 7 in the sleeve 17 under the axial pressure exerted by a resilientmember 20, more particularly, a helical spring, in such a way that thenozzle stem 3 again is held therein as in a chuck. Thus, it is possibleto unscrew member 9 for removal of members 20, i, 2, 3, 5, while ring 19remains in its position and retains the member 17', so that the coolingwater is safely prevented from entering into the cylinder. It will beappreciated that a very effective cooling of the nozzle is ensured inthis case together with a simple construction and method of assemblingand dismantling the parts.

While the invention has been described in detail with respect to certainnow preferred examples and embodiments of the invention it will beunderstood by those skilled in the art after understanding the inventionthat various changes and modifications may be made without departingfrom the spirit and scope of the invention and it is intended,therefore, to cover all such changes and 'lOdlfiCZl'ElOllS in theappended claims.

I claim:

1. A cylinder head and injection nozzle arrangement for internalcombustion engines, comprising a cylinder head, steeply tapered conicalnozzle bore means in said cylinder head, an injection nozzle including anozzle stem, a similarly tapered conical packing body of a higherthermal conductivity than said injection nozzle surrounding saidinjection nozzle and adapted to be freely slipped on the nozzle stem ina dismantled condition and being 'llush with the free end of said nozzlestem, and resilient means for forcing the conical packing body into saidconical nozzle bore of the cylinder head, in such a way that the conicalpacking body in an assembled condition fits tightly in the conical boreof the cylinder head and when heated fits tightly on the nozzle stem.

2. A cylinder head and injection nozzle arrangement for internalcombustion engines, comprising a cylinder head formed with a conicalnozzle bore, an injection nozzle including a nozzle stem, a nozzleholder, :1 conical packing body of a high thermal conductivity adaptedto be freely slipped on the nozzle stem in a dismantled condition, andmeans including an axially resilient mernher for transmitting axialforces onto the conical packing body for forcing said body into saidconical nozzle bore of the cylinder head, in such a way that the conicalpacking body in an assembled condition fits tightly in the conical boreof the cylinder head and on the nozzle stem.

3. An arrangement as in claim 1, further comprising a cooling waterchamber in said cylinder head communicating with said tapered conicalnozzle bore, and a sleevelike extension on said packing body reachinginto said cooling chamber to be washed by the cooling water therein.

4. An arrangement as in claim 3, said resilient means further comprisinga force-transmitting sleeve engaging said sleeve-like extension.

5. An arrangement as in claim 1, a cooling water chamber in saidcylinder head surrounding said resilient means, said resilient meansfurther comprising a sleevelike extension on said packing body, a nozzleholder mounted in said cylinder head and being surrounded by saidsleeve-like extension, and means for exerting an axial pressure on saidextension to effect a chuck clamping of said nozzle stem by said packingbody.

6. An arrangement as in claim 5, said exerting means further comprisinga ring nut threaded to said cylinder head and surrounding said nozzleholder, and elastic means mounted between said nut and the end of saidsleeve-like extension.

7. An arrangement as in claim 6, said elastic means further comprisingan expanding ring.

8. An arrangement as in claim 1, further comprising a cooling waterchamber in said cylinder head surrounding said injection nozzle, anozzle holder engaging said packing body, a ring nut threaded to saidcylinder head, said resilient means being interposed between said ringnut and said nozzle holder and a sleeve having a conical end seated insaid conical bore means and surrounding said packing body and extendinginto contact with said ring nut.

References Cited in the file of this patent UNITED STATES PATENTS1,653,287 Johnson Dec. 20, 1927 2,080,189 Schwaiger May 11, 19372,144,861 Truxell Jan. 24, 1939 2,322,606 Ward June 22, 1943 2,560,799Johnson July 17, 1951

